Start at 125% for a modest increase, or 75% to make a recording quieter. Keep your device volume unchanged while comparing the original and output. Mediaivo changes the file’s gain and exports MP3; it does not automatically balance speakers, remove background noise or normalize to a loudness target.
Adjust the recording, then listen
Choose a gain setting and create a separate MP3 copy. The real speech comparison below is available before you upload your own file.
What 125%, 150% and 200% actually mean
The percentage multiplies the audio amplitude. It is not a percentage of perceived loudness. Doubling amplitude adds about 6 dB; it does not mean that every listener hears the sound as twice as loud.
| Setting | Gain change | Practical use |
|---|---|---|
| 50% | −6.02 dB | A substantial reduction. |
| 75% | −2.50 dB | A modest reduction. |
| 125% | +1.94 dB | A cautious first increase. |
| 150% | +3.52 dB | More gain when the source has headroom. |
| 200% | +6.02 dB | A large increase; inspect the loudest phrase. |
Check headroom before increasing gain
If an input peaks at −1 dBFS, 125% adds about 1.94 dB and can push its peaks above full scale. A quieter passage does not tell you how much room the loudest peak has. Start with the loudest word, laugh or transient, then listen through the rest.
Gain raises background hiss and room noise together with the voice. If noise is the main problem, a stronger gain setting will not separate it from speech. Lowering an already clipped recording makes the distortion quieter but does not restore the lost waveform.
How to adjust volume with Mediaivo
- Keep the original. Upload your best audio copy to Change Audio Volume.
- Choose the smallest useful change. Try 125% for a quiet file or 75% for a reduction.
- Process and download. The output is MP3, including when your input was WAV. Encoding can change peaks slightly.
- Compare at the same device setting. Listen to loud and quiet passages. Check for crackling, harsh consonants and raised background noise.
Gain, device volume and normalization are different
Your phone’s volume setting changes local playback. File gain changes the exported recording. Loudness normalization measures a loudness target and requires different processing. This tool applies one gain multiplier to the whole recording; it does not make every word equally loud.
Use Trim Audio for unwanted sections or Convert Audio when the main task is a different format. For the underlying operation, see FFmpeg’s volume filter.
Questions before exporting
Can I boost an MP3 without changing quality?
Mediaivo re-encodes the output as MP3. Keep the original and avoid repeatedly boosting downloaded copies.
Is 200% safe for any recording?
No. A source already near full scale may distort. Compare the loudest passage and use less gain if needed.
Can this repair a quiet speaker beside a loud speaker?
It applies the same multiplier throughout. Balancing different speakers needs editing or dynamics processing beyond this tool.
Try the speech source in the tool, or compare the downloadable speech and synthetic-tone measurements below.
Hear gain changes on a human voice
A 12-second human narration excerpt, deliberately reduced to 35% amplitude to make a quiet input. Keep your device volume low and unchanged while comparing. Playback starts only when you press play.
| File | Peak (dBFS) | RMS (dBFS) | Full-scale samples |
|---|---|---|---|
| Quiet source | -15.44 | -31.42 | 0 |
| Speech · 125% | -13.57 | -29.48 | 0 |
| Speech · 200% | -9.39 | -25.4 | 0 |
125% adds about 1.94 dB; 200% adds about 6.02 dB before encoding. This example stays below full scale. Louder source recordings can clip: gain does not remove noise, repair distortion or normalize loudness.
Download input · Download output
Try Speech · 125% in the tool →
Download input · Download output
Try Speech · 200% in the tool →
Source: Alice’s Adventures in Wonderland, Chapter 1 — Lewis Carroll; read by Kristen McQuillin for LibriVox. Public-domain recording released by LibriVox. Excerpt 00:35–00:47, decoded to mono 48 kHz WAV, amplitude multiplied by 0.35 to prepare a quiet example. Outputs exported as MP3 at 125% and 200%.
Processed with the same Mediaivo tool code. Measurements, settings and SHA-256 hashes · Credits and reuse terms. One short nature clip and one prepared speech excerpt. These results do not represent every phone, speaker, codec, recording or scene. No claim of lossless compression, noise removal, loudness normalization or endorsement by the source creators.
Compare 100%, 125% and 75% on the same audio
Start at a low device volume. This four-second synthetic reference tone is not speech or music. Keep your speaker or headphone setting unchanged while comparing the files; nothing plays automatically.
| File | Sample peak (dBFS) | RMS (dBFS) | Samples at or above full scale |
|---|---|---|---|
| Source WAV · 100% | -9.12 | -16.11 | 0 |
| Output MP3 · 125% | -7.18 | -14.17 | 0 |
| Output MP3 · 75% | -11.57 | -18.61 | 0 |
Download input · Download 125% amplitude output
Try 125% amplitude in the tool →
Download input · Download 75% amplitude output
Try 75% amplitude in the tool →
Gain is not loudness normalization
125% multiplies amplitude by 1.25 (about +1.94 dB); 75% applies 0.75 (about −2.50 dB). MP3 encoding can slightly change peaks. These references stay below full scale, but that does not prove every recording is distortion-free. The tool applies gain and exports MP3; it does not target a LUFS loudness, remove noise or repair clipping already in the source.
For an input peaking at −1 dBFS, adding +1.94 dB can push peaks above full scale. Listen to your loudest phrase before keeping an increase. Use Trim Audio for unwanted sections and Convert Audio when your main goal is a different format.
Measured with the actual Mediaivo processor. Settings, file hashes and encoder version · Test pack and method. Results can vary with the source and encoder version.